using System;

using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.X509;

namespace Org.BouncyCastle.Asn1.Cms
{
	public class OriginatorPublicKey
		: Asn1Encodable
	{
		private AlgorithmIdentifier algorithm;
		private DerBitString        publicKey;

		public OriginatorPublicKey(
			AlgorithmIdentifier algorithm,
			byte[]              publicKey)
		{
			this.algorithm = algorithm;
			this.publicKey = new DerBitString(publicKey);
		}

		public OriginatorPublicKey(
			Asn1Sequence seq)
		{
			algorithm = AlgorithmIdentifier.GetInstance(seq[0]);
			publicKey = (DerBitString) seq[1];
		}

		/**
		 * return an OriginatorPublicKey object from a tagged object.
		 *
		 * @param obj the tagged object holding the object we want.
		 * @param explicitly true if the object is meant to be explicitly
		 *              tagged false otherwise.
		 * @exception ArgumentException if the object held by the
		 *          tagged object cannot be converted.
		 */
		public static OriginatorPublicKey GetInstance(
			Asn1TaggedObject	obj,
			bool				explicitly)
		{
			return GetInstance(Asn1Sequence.GetInstance(obj, explicitly));
		}

		/**
		 * return an OriginatorPublicKey object from the given object.
		 *
		 * @param obj the object we want converted.
		 * @exception ArgumentException if the object cannot be converted.
		 */
		public static OriginatorPublicKey GetInstance(
			object obj)
		{
			if (obj == null || obj is OriginatorPublicKey)
				return (OriginatorPublicKey)obj;

			if (obj is Asn1Sequence)
				return new OriginatorPublicKey((Asn1Sequence) obj);

			throw new ArgumentException("Invalid OriginatorPublicKey: " + obj.GetType().Name);
		}

		public AlgorithmIdentifier Algorithm
		{
			get { return algorithm; }
		}

		public DerBitString PublicKey
		{
			get { return publicKey; }
		}

		/**
		 * Produce an object suitable for an Asn1OutputStream.
		 * <pre>
		 * OriginatorPublicKey ::= Sequence {
		 *     algorithm AlgorithmIdentifier,
		 *     publicKey BIT STRING
		 * }
		 * </pre>
		 */
		public override Asn1Object ToAsn1Object()
		{
			return new DerSequence(algorithm, publicKey);
		}
	}
}
